Abstract: A pipe flange alignment guide to assist in connection of adjoining bolted pipe flanges is described. The guide is comprised of first and second semi-circular body sections joined together by a clamshell hinge and a buckle assembly. Each body section has a flared bottom that forms a conical opening when the body sections are positioned around adjoining flanged pipe segments. The top of each body section forms a semi-circular cover with opening edges having a plurality of spaced apart scallops. The scallops conform to the bolt hole pattern of the adjoining pipe flanges and serve as an alignment guide for the flange attachment bolts.